Without limiting the scope of the present invention, its background will be described with reference to fluid production from a hydrocarbon bearing subterranean formation, as an example. During the completion of a well that traverses a hydrocarbon bearing subterranean formation, production tubing and various completion equipment are installed in the well to enable safe and efficient production of the formation fluids. For example, to prevent the production of particulate material from an unconsolidated or loosely consolidated subterranean formation, certain completions include one or more sand control screens positioned proximate the desired production intervals. In other completions, to control the flow rate of production fluids into the production tubing, it is common practice to install one or more flow control devices within the tubing string.
Attempts have been made to utilize fluid flow control devices within completions requiring sand control. For example, in certain sand control screens, after production fluids flows through the filter medium, the fluids are directed into a flow control section. The flow control section may include one or more flow restrictors such as flow tubes, nozzles, labyrinths or the like. Typically, the production rate through these flow control screens is fixed prior to installation by adjusting flow restrictors in the flow control section.
It has been found, however, that due to changes in formation pressure and changes in formation fluid composition over the life of the well, it may be desirable to adjust the flow control characteristics of the flow control screens. In addition, for certain completions, such as long horizontal completions having numerous production intervals or zones, it may be desirable to independently control the inflow of production fluids into each of the production intervals.
Accordingly, a need has arisen for a flow control screen that is operable to control the inflow of formation fluids in a completion requiring sand control. A need has also arisen for such a flow control screen that is operable to adjustably control the inflow of formation fluids as the fluid characteristics of production change over time. Further, a need has arisen for such flow control screens that are operable to independently control the inflow of production fluids from multiple production intervals as the composition of the fluids produced into specific intervals changes over time.